predatory plecos?

minmin · Post by **minmin** » 20 Oct 2005, 09:13

i really like the pseudocanthicus type plecs, and in all the writing on them it says they are more carnivores, but not predatory.

now i was just wondering, is there a predatory pleco, rather than just a carnivorous scavanger?

Yann · Post by **Yann** » 20 Oct 2005, 10:41

Hi!

No not at all...

Cheers
Yann

pturley · Post by **pturley** » 20 Oct 2005, 15:22

Actually, they are.

The fact that Pseudacanthicus actively seek out and feed upon mollusks and crustraceans (snails, clams, shrimp and prawns) does qualify them as a "predator". But they are clearly also a scavenger as well.

A very good example of a predatory Loricariid would be Spatuloricaria spp.. These are very aggressive feeders when live Mystis shrimp are added to the tank. Even to the point of rolling over largish (2-3" diameter x 1/4-1/2" thick) stones to uncover the shrimp beneath.

So yes, there are predatory Loricariids.

MatsP · Post by **MatsP** » 20 Oct 2005, 15:36

I agree with Paul, there are certainly plecos that go after live food. Even "peaceful" plecos like bristlenoses will go after for instance blood-worms, activiely chasing after ones that are trying to escape.

However, I'm not aware of any pleco that will go after healthy, reasonably large fish. They may well eat baby-fish if the babies aren't clever/fast enough to swim away, and they certainly _WILL_ eat dead/dying fish if there are any nearby.

--
Mats

pturley · Post by **pturley** » 20 Oct 2005, 17:16

Large Scobinancistrus auratus will actively feed on "feeder goldfish" and other small fishes.
I don't know if this is a behavior they would exhibit in the wild, but they certainly do in an aquarium.

H.N · Post by **H.N** » 20 Oct 2005, 17:20

Scobinancistrus eat othe fish skin with their unique teeth.
That is why I think they are very different to Panaque.
Scobinancistrus ambush other fish come nearby and snich off
prey skin.
Pseudacanthicus eat whole freshwater bivalves and digest
flesh. Undigested shells will come out afterward. During
seasonal big shelfish bloom in shallow area, they actively
consume these bivalves during night.
A lot of insectivour loricariids are also known.

Yann · Post by **Yann** » 20 Oct 2005, 19:20

Ok!

I didn't know this about Scobinancistrus...
But I wouldn't consider predatory against insect larvae, crustacea as predatory the way that most would think of... minmin was (I think) thinking at predatory against other fish...
so until now we would only have Scobinancistrus!
Cheers
Yann

L-14 · Post by **L-14** » 21 Oct 2005, 13:01

Ones I keep as adults don't seem to try that. They share the tank with large danios [3 inches], small barbs and Geophagus cichlids. Their previous pleco tankmates [that were moved to other tanks later on] never got hunted either.

They do bite nastily when fighting for preferred cave though, with large area on the top of tail section peeled off leaving white underneath...

What about Leporacanthicus? What is its diet in the wild?

pturley · Post by **pturley** » 21 Oct 2005, 15:09

L-14 Wrote:

What about Leporacanthicus? What is its diet in the wild?

I had actually typed this in my original reply but removed it for the sake of brevity.
It's my understanding that the diet of Leporacanthicus spp. is nearly identical to that of Pseudocanthicus spp.. Mollusks, insect larvae, crustaceans and likely freshwater sponges making up the bulk of the intake.

To be quite honest, in alot of these fish the content of their stomaches(gut analysis) of specimens collected in the wild has yet to be published. Though it's often published in the original species descriptions.
That said, please note the information above is second hand info., not taken directly from published text.

H.N. do you have any references for the feeding behavior you described above for Scobinancistrus?

Was this in the species description?

L-14 · Post by **L-14** » 21 Oct 2005, 16:49

I haven't go back to read the OD but OD of sunshine IIRC didn't mention the stomach contents but gave opinion about its diet.

H.N · Post by **H.N** » 21 Oct 2005, 19:32

>Yann
Since the term "predatory" was not defined here, I just list what might be. Glad to hear you found one from my list.

>L14
It would be difficult to see skin eating behaviour in aquarium tank because they get
enough food all the time. Like too much protein for Panaque makes them stop feeding
wood in the tank. Some of my friends say seeing scraches on their Scobinancistrus in dence tank condition.

>pturley
Not in papers. it is from my personal communication with Don J. Stewart (and others).
Gut content studies in neotropic fish are usually done only during dry seasons, so
I am not 100% confidence on these inf.